Manhole cover



o. c. ELBERT.

MANHOLE COVER.

APPLICATION FILED NOV.15, 1920.

Patentedi Dec. 12, 1922.

|NvENToR l F .5 BY

ATTORNEY Patented Een. fiialgl.

ll lil ll La"l" tl d ri l OTTO C. ELBEBT, OF BREMERTON, WASHIGTON'.

, y N tiran MANHOLE CGVER.

Application led November ,15, 1920. Serial No. 424,057.

tached over a man hole in a tank or container and held thereto in afixed and leakf proof position by one screw.

rIhese and other objects will appear as my invention is hereinafter morefully set forth in the following specification, shown in theaccompanying drawings and finally pointed out in the appended claims.

ln the drawings:

Fig. 1 is a top view showing the coverl attached to asection of a tankor container.

Fig. 2 is a cross sectional'side view of the cover and its locking meanstaken upon the line 2-2 of Fig. 1.

Fig. 3 indicates an annular flange attached to a section of a tank orcontainer.

Fig. e' is a bottom view of the cover.

Fig. 5 is a top view of a resilient separatingwasher. j

Referring now more particularly to the drawings:

Reference numeral l. indicates a section of a tank or container formedwith a hole 2 and whose periphery is surrounded by an annular flange 3formed ywith holes 4 which are in alignment with corresponding holes inthe tanl: 1, through which bolts or rivets pass used in attaching theannular flange to a tank or container in a leakproof manner. The upperface ofthe annular flange 3 is formed with an annular depression 5 whichreceives a cover 6, said cover being formed with a square hole 7. In thebottom of the depression 5 of the said annular flange andy integraltherewith is a stop pin 8 whose one end extends below the bottomsurfaceof said flange, the periphery of the flange opening being formed withcut-out portions 9. 10 is a locking plate whoseouter periphery is formedwith semi-Circular projections 11. Disposed in the central portion ofsaid plate is a square hole 12. Intermediate the locking plate 10 andthe cover 6 is an espe-- cially resilient washer 13, formed with asquared hole 14; in' its central portion and a plurality of rectangularnotches 15 in its periphery the portions 16 in between said notchesbeing alternately bent upwardly and .c downwardly, to provide portionsdesigned for contact with the bottom of the cover 6 and portionsdesigned for contact' with the upper faceof the locking plate 10generally shown in Fig. 2. Intermediate the resilient washer 13 and thecover 6 is a rubber washer, 17. 18 is a heXagon head screw.

portion 20 above the said square being circular and formed with a thread21, the lock-` ing plate 10, the resilient washer 13, the rubber washer17 and the cover 6 being slidably mounted on the square portion 19 ofthe bolt v18 and kept thereon by a pin 22which is forced into a lateralhole28 in the circular portion 2O adj acentthe square portion 19 of thescrew 18 generally shownl in, Fig. 2. 24C is a resilient washer whose'divergingedge 25 holds the horizontal portion thereon in a spacedrelation with the cover 6, the hori- Zontal portion being formed with acircular hole 26. The vperiphery of the said resilient washer is formedheXagonas shown at 27 in 1, thecorners thereof4 being notched at 28 asshown in F-igs. 1 and 2, said washer being slidably mountedon the`threaded portion 21 of the screw 18.

.having a square portion as at 197 the upper Threadedly mounted on thethreaded por- I tion 21 of said screw is a heXagon nut 29.

1n the operation of a cover as herein described, it can readily beunderstood that `when a tank or container opening has an annular flangeof the construction as herein described surrounding the periphery of thesaid opening and rigidly attached thereto that the projections 11 of thelocking plate 10 are free to pass downward through the cut-out portions9 in said flange subsequentlylallowing the plate 6 to restin ythedepression 5 in said flange. The plate 10 is then rotated in thedirection of the arrow as indicated at Fig. 3 until one oftheprojections 11 come in contact with the stop pin 8.v The projections 11of the locking plate 10 will then be underneath the projections inbetween the cut-out portions 9 of the said annular flange. The nut 29whichis threadedly mounted on the bolt 18 is rotated to" bring thelocking plate in Contact with the bottom face of the said annular flangeit being understood'that thecover G'cannot revolve, because qt itsrelation with the squared portion 19 in a likewise manner in respect tothe locking plate l0. vWhen a suliicient tension has been applied to thelocking plate l0 so as `to hold it in a fixed relation with the saidannular ange, it can be seen that the divergent edges of the resilientvwasher 25 will hold the cover 6 in a leakproof relation with the saidannular flange. When it is desired to remove the cover f3 from the saidflange this is accomplished by releasing Vthe tension of the loclringplate l0 by unscrewing` the nut 29, subsequentb7 allowing the resilientwasher 16 to bring the locking plate l0 downward out of engagement withthe said flange. ift will then'be seen that when the locking plate isrelieved of its tension that the cover@ will move away from the pin 8,which of course will let the operator know that the cover is free to beremoved, said cover being removed by arranging the projections lll ofthe plate 10 in position to pass' through the cut-out portions 9 of thesaid flange.

l/Vhile l' have shown'a particuleul form of embodiment of my invention,l' am aware that man3T minor changes therein will readily suggest'tiemselves to others skilled in the art, without departing Vrein thespirit and scope of kmy invention. li therefore desire to avoidbeinglimited to the exact form shown and described.

Having described my invention, what l claim as new and desire to protectb v Letters rPatent', is:

l. In combination with a tank or container having an opening, of anannular flange attached'to said container in line with the opening, aportion of said flange being formed to receive the cover proper1 andhaving an edge formation of spaced cut-out portions, a cover to restupon said projecting portion of theflange, a locking plate havingperipheral projections adapted te pass thru the cut-out portions of theflange and to be mounted for rotative movement with respect to theflange to dispose the projections of said locking plate intermediate thecnt-out portions of the flange, a resilient washer interposed betweenthe locking plate and cover, and means for drawing said locking plateand cover toward each other, whereby the locking plate may be secured incover-locking relation to the flange.

2. ln combination with a tank or container havingr an opening, of anannular flange attached to said container in line with the opening, aportion of said flange being formed to receive the cover proper andhaving .an edge formation oi spaced cut-out portions, a 'cover to restupon saidv projecting portion of the flange, a locking plate ravingperipheral projections adapted to pass thru the cut-out portions of theflange and to be mounted for rotative movement with respect to theflange to dispose the projections of said locking plate intermediate thecut-out portions of theV flange, a resilient washer interposed betweenthe locking plate and cover, means for drawing said locking plate andcover toward each other, whereby the locking plate may be secured vincoverlocking relation to the flange, and means on said flange to limitthe` rotative movement of the locking plate with respect to the flange,

ln testimony whereof l my signature in the presence of two witnesses.

OTT@ C. ELBERT.

